Kevin Hart and Olivia Munn are co-stars in the buddy comedy “Ride Along 2,” but on Thursday’s “Lip Sync Battle” they were mortal enemies.

The pair’s competitive nature was in full effect before either contestant had even performed, with Munn complaining that Hart got a louder applause when they were introduced by host LL Cool J than she did.

However, her opening act to Nelly and Kelly Rowland’s 2002 hit song, “Dilemma,” saw the actress rapping Nelly’s verses and singing Rowland’s chorus in a performance that was praised by even her rival for its “creativity.”

Pint-sized star Hart then counteracted with a smoking hot rendition of “OMG” by Usher. “The thing with Usher is there’s a lot of pointing and grabbing,” he complained, after nearly pulling a muscle dancing.

In a cutting reference to Channing Tatum‘s wild card by pulling out Beyonce to help him pull off a brilliant performance of “Run the World (Girls)” last week, the comedian told the camera backstage: “No guest appearances, Kevin Hart rolls by himself, Kevin Hart doesn’t play that sh–t.”

Instead, he rocked out on stage with a dance crew — and a bouncing car — for “Slam (Let the Boys be Boys)” by Onyx, complete with stage-diving audience members jumping into the throng.

The “Mortdecai” star then went for hit-maker Taylor Swift‘s “Bad Blood,” strutting across the stage in a white jumpsuit, thigh-high boots and shiny gun, along with a very sultry expression and a dancer beefy enough to be Swift’s bodyguard.